EMC2301 Standard Microsystems Corp., EMC2301 Datasheet - Page 26

• Manufacturer Part Number: EMC2301
• Description: Rpm-based Pwm Fan Controller
• Manufacturer: Standard Microsystems Corp.

ADDR
26h
27h
Revision 1.2 (03-22-10)
R/W
R-C
R-C
5.3.1
5.3.2
5.3.3
5.3.4
REGISTER
Fail Status
Fan Drive
Fan Spin
Status
The Fan Status registers contain the status bits associated with the fan driver.
Fan Status - 24h
The Fan Status register indicates that the fan driver has stalled or failed or that the Watchdog Timer
has expired (see
Bit 7 - WATCH - Indicates that the Watchdog Timer has expired. When set, the fan is driven to 100%
duty cycle and will remain at 100% duty cycle until it is programmed. This bit is cleared when it is read.
Bit 2 - DRIVE_FAIL - Indicates that the fan driver cannot meet the programmed fan speed at maximum
PWM duty cycle. This bit is set when the DRIVE_FAIL bit is set (in the Fan Drive Fail Status register).
This bit is cleared when the DRIVE_FAIL bit is cleared.
Bit 1 - FAN_SPIN - Indicates that the fan driver cannot spin up. This bit is set when the FAN_SPIN bit
is set (in the Fan Spin Status register). This bit is cleared when the FAN_SPIN bit is cleared.
Bit 0 - FAN_STALL - Indicates that the fan driver have stalled. This bit is set when the FAN_STALL bit
is set (in the Fan Stall Status register). This bit is cleared when the FAN_STALL bit is cleared.
Fan Stall Status - 25h
The Fan Stall Status register indicates that the fan driver has detected a stalled condition (see
Section
Bit 0 - FAN_STALL - Indicates that the Fan has stalled.
Fan Spin Status - 26h
The Fan Spin Status register indicates that the fan driver has failed to spin-up (see
bit is cleared upon a read if the error condition has been removed.
Bit 0 - FAN_SPIN - Indicates that the Fan has failed to spin up.
Fan Drive Fail Status - 27h
The Fan Drive Fail Status register indicates that the fan driver cannot drive to the programmed speed
even at 100% duty cycle (see
error condition has been removed.
Bit 0 - DRIVE_FAIL1 - Indicates that the Fan cannot reach its programmed fan speed even at 100%
duty cycle. This may be due to an aging fan or invalid programming.
4.4.1). This bit is cleared upon a read if the error condition has been removed.
B7
-
-
Section
Table 5.3 Fan Status Registers (continued)
B6
4.8).
-
-
Section 4.4.2
DATASHEET
B5
-
-
26
and
B4
-
-
Section
5.12). This bit is cleared upon a read if the
B3
-
-
B2
-
-
RPM-Based PWM Fan Controller
B1
-
-
Section
SMSC EMC2301
DRIVE_
Datasheet
4.6). This
FAN_
SPIN
FAIL
B0
DEFAULT
00h
00h